lost my Sailfin Goby Coral beauty now in hiding

[one-fish]

Bad News Goby died yesterday morning woke to find it laying in the rocks grayish color not moving since then it was eating well and was getting used to the tank and his new tank-mates all seemed well until yesterday this morning had to find the coral beauty very odd that fish is usually greeting me when the lights come on It stayed hiding in the rocks when I fed the others and still remains hiding I can see it breathing but it is just hovering around under the rocks not swimming like it's self Did do a WC Sat afternoon only 15 gals everything was normal all Sunday and Monday All fish ate and acting normal Tested water today all levels good slight increase in PH from 8.1to 8.3 all other tests were as a week ago before the WC This is the first fish I have lost not sure what to do something is not right can't see anywhere I may have caused this ??another bigger WC??? or just wait it out and observe the fish more

 

[one-fish]

Looks like this fish will not see another day Sad!!! had her for over a year now both clowns and both chromis doing fine Just wish I knew WHY What did I do wrong ?? Just Depressed.!!!

 

[jay0705]

Did you stir up the sand at all when you did the w c?

 

[one-fish]

no but did clean out the sump left sand bed in DT alone know not to do that cuz it may release build up of toxic gases deep in the sand bed sump had alot of GHA competing w/the caulerpa coral beauty did die but other fish seem fine Just wish I knew what caused the two deaths thinking of doing a 20 gal WC in a couple of days This tank has been running for a month now. All water parameters have been steady after it was cycled only change I saw was the PH 8.1to8.3 that's normal due to the new water NO3 also dropped from 10ppm to 5ppm again normal due to WC just don't know

 

[one-fish]

Because I've not found any answer as to what may have caused the two sudden fish deathsI've made up new water and filled my 10 gal QTtank 1.)



for the new coral beauty I want to add and 2.) just it case I see another fish acting abnormally I have 6lbs of ceramic cylinders used as bio media in the sump which has been running for a month and a dual sponge filter running now for a week to act as a temporary bio filter if I need to place fish inside the QT since it is not cycled that along with constant amm. monitoring I should be okay I can always throw in some rock from the DT if needed and hope whatever killed the fish isn't present in the rock or bio media What to Do ?? wife says that the clowns look sad and they miss their friend the coral beautyTHEY'VE been together for a year now guess that's possible Just don't want to lose anymore I've had the clowns now for 2 years... Sad now.. but hoping for the best...Anyone else have any other suggestions Pls help THX...